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Abstract Background Drug resistance in Plasmodium falciparum is a major threat to malaria control efforts. Pathogen genomic surveillance could be invaluable for monitoring current and emerging parasite drug resistance. Methods Data from two decades (2000–2020) of continuous molecular surveillance of P. falciparum parasites from Senegal were retrospectively examined to assess historical changes in malaria drug resistance mutations. Several known drug resistance markers and their surrounding haplotypes were profiled using a combination of single nucleotide polymorphism (SNP) molecular surveillance and whole genome sequence based population genomics. Results This dataset was used to track temporal changes in drug resistance markers whose timing correspond to historically significant events such as the withdrawal of chloroquine (CQ) and the introduction of sulfadoxine-pyrimethamine (SP) in 2003. Changes in the mutation frequency at Pfcrt K76T and Pfdhps A437G coinciding with the 2014 introduction of seasonal malaria chemoprevention (SMC) in Senegal were observed. In 2014, the frequency of Pfcrt K76T increased while the frequency of Pfdhps A437G declined. Haplotype-based analyses of Pfcrt K76T showed that this rapid increase was due to a recent selective sweep that started after 2014. Discussion (Conclusion) The rapid increase in Pfcrt K76T is troubling and could be a sign of emerging amodiaquine (AQ) resistance in Senegal. Emerging AQ resistance may threaten the future clinical efficacy of artesunate-amodiaquine (ASAQ) and AQ-dependent SMC chemoprevention. These results highlight the potential of molecular surveillance for detecting rapid changes in parasite populations and stress the need to monitor the effectiveness of AQ as a partner drug for artemisinin-based combination therapy (ACT) and for chemoprevention.

Background. Globally, approximately 20% of malignancy are caused by infection. Schistosoma infection is a major cause of bladder in most part of Africa. In 2018 alone, there were approximately 549,393 new cases and 199,922 deaths from bladder cancer. The presence of Schistosoma ova in the venous plexus of the bladder induces a cascade of inflammation causing significant tissue damage and granulomatous changes. Methodology. A literature review was conducted from 1995 to 2019 using PubMed, Google Scholar, African Journal Online, and Google databases. Relevant data on the association of “Schistosomiasis and Bladder cancer” in sub-Saharan Africa (SSA) were retrieved. Evidence Synthesis. Results from research using animal models to establish the carcinogenesis of Schistosoma and bladder cancer have been helpful but inconclusive. Immunoregulatory cytokines and genetic marker have been identified to play a role in the pathogenesis. In some parts of sub-Saharan Africa, there has been close association of squamous cell carcinoma and histological evidence of Schistosoma ova. Conclusion. There are some data to support the association between schistosomiasis and bladder cancer in sub-Saharan Africa. However, these have been limited by their design and may not sufficiently establish carcinogenesis. There is a need for more genomic and molecular research to better characterize S. haematobium and its effects on the bladder. Such goal will contribute immensely to Schistosoma bladder cancer prevention and control.